Float
public
final
class
Float
extends Number
implements
Comparable<Float>
java.lang.Object | ||
↳ | java.lang.Number | |
↳ | java.lang.Float |
The Float
class wraps a value of primitive type
float
in an object. An object of type
Float
contains a single field whose type is
float
.
In addition, this class provides several methods for converting a
float
to a String
and a
String
to a float
, as well as other
constants and methods useful when dealing with a
float
.
Floating-point Equality, Equivalence, and Comparison
The classjava.lang.Double
has a discussion of equality,
equivalence, and comparison of floating-point values that is
equality applicable to float
values.
Summary
Constants | |
---|---|
int |
BYTES
The number of bytes used to represent a |
int |
MAX_EXPONENT
Maximum exponent a finite |
float |
MAX_VALUE
A constant holding the largest positive finite value of type
|
int |
MIN_EXPONENT
Minimum exponent a normalized |
float |
MIN_NORMAL
A constant holding the smallest positive normal value of type
|
float |
MIN_VALUE
A constant holding the smallest positive nonzero value of type
|
float |
NEGATIVE_INFINITY
A constant holding the negative infinity of type
|
float |
NaN
A constant holding a Not-a-Number (NaN) value of type
|
float |
POSITIVE_INFINITY
A constant holding the positive infinity of type
|
int |
PRECISION
The number of bits in the significand of a |
int |
SIZE
The number of bits used to represent a |
Fields | |
---|---|
public
static
final
Class<Float> |
TYPE
The |
Public constructors | |
---|---|
Float(float value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. The static factory
|
|
Float(double value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. Instead, use the
static factory method |
|
Float(String s)
This constructor is deprecated.
It is rarely appropriate to use this constructor.
Use |
Public methods | |
---|---|
byte
|
byteValue()
Returns the value of this |
static
int
|
compare(float f1, float f2)
Compares the two specified |
int
|
compareTo(Float anotherFloat)
Compares two |
double
|
doubleValue()
Returns the value of this |
boolean
|
equals(Object obj)
Compares this object against the specified object. |
static
int
|
floatToIntBits(float value)
Returns a representation of the specified floating-point value according to the IEEE 754 floating-point "single format" bit layout. |
static
int
|
floatToRawIntBits(float value)
Returns a representation of the specified floating-point value according to the IEEE 754 floating-point "single format" bit layout, preserving Not-a-Number (NaN) values. |
float
|
floatValue()
Returns the |
int
|
hashCode()
Returns a hash code for this |
static
int
|
hashCode(float value)
Returns a hash code for a |
static
float
|
intBitsToFloat(int bits)
Returns the |
int
|
intValue()
Returns the value of this |
static
boolean
|
isFinite(float f)
Returns |
boolean
|
isInfinite()
Returns |
static
boolean
|
isInfinite(float v)
Returns |
static
boolean
|
isNaN(float v)
Returns |
boolean
|
isNaN()
Returns |
long
|
longValue()
Returns value of this |
static
float
|
max(float a, float b)
Returns the greater of two |
static
float
|
min(float a, float b)
Returns the smaller of two |
static
float
|
parseFloat(String s)
Returns a new |
short
|
shortValue()
Returns the value of this |
static
float
|
sum(float a, float b)
Adds two |
static
String
|
toHexString(float f)
Returns a hexadecimal string representation of the
|
String
|
toString()
Returns a string representation of this |
static
String
|
toString(float f)
Returns a string representation of the |
static
Float
|
valueOf(String s)
Returns a |
static
Float
|
valueOf(float f)
Returns a |
Inherited methods | |
---|---|
Constants
BYTES
public static final int BYTES
The number of bytes used to represent a float
value.
Constant Value: 4 (0x00000004)
MAX_EXPONENT
public static final int MAX_EXPONENT
Maximum exponent a finite float
variable may have. It
is equal to the value returned by Math.getExponent(Float.MAX_VALUE)
.
Constant Value: 127 (0x0000007f)
MAX_VALUE
public static final float MAX_VALUE
A constant holding the largest positive finite value of type
float
, (2-2-23)·2127.
It is equal to the hexadecimal floating-point literal
0x1.fffffeP+127f
and also equal to
Float.intBitsToFloat(0x7f7fffff)
.
Constant Value: 3.4028235E38
MIN_EXPONENT
public static final int MIN_EXPONENT
Minimum exponent a normalized float
variable may have.
It is equal to the value returned by Math.getExponent(Float.MIN_NORMAL)
.
Constant Value: -126 (0xffffff82)
MIN_NORMAL
public static final float MIN_NORMAL
A constant holding the smallest positive normal value of type
float
, 2-126. It is equal to the
hexadecimal floating-point literal 0x1.0p-126f
and also
equal to Float.intBitsToFloat(0x00800000)
.
Constant Value: 1.1754944E-38
MIN_VALUE
public static final float MIN_VALUE
A constant holding the smallest positive nonzero value of type
float
, 2-149. It is equal to the
hexadecimal floating-point literal 0x0.000002P-126f
and also equal to Float.intBitsToFloat(0x1)
.
Constant Value: 1.4E-45
NEGATIVE_INFINITY
public static final float NEGATIVE_INFINITY
A constant holding the negative infinity of type
float
. It is equal to the value returned by
Float.intBitsToFloat(0xff800000)
.
Constant Value: -Infinity
NaN
public static final float NaN
A constant holding a Not-a-Number (NaN) value of type
float
. It is equivalent to the value returned by
Float.intBitsToFloat(0x7fc00000)
.
Constant Value: NaN
POSITIVE_INFINITY
public static final float POSITIVE_INFINITY
A constant holding the positive infinity of type
float
. It is equal to the value returned by
Float.intBitsToFloat(0x7f800000)
.
Constant Value: Infinity
PRECISION
public static final int PRECISION
The number of bits in the significand of a float
value.
This is the parameter N in section {@jls 4.2.3} of
The Java Language Specification.
Constant Value: 24 (0x00000018)
SIZE
public static final int SIZE
The number of bits used to represent a float
value.
Constant Value: 32 (0x00000020)
Fields
TYPE
public static final Class<Float> TYPE
The Class
instance representing the primitive type
float
.
Public constructors
Float
public Float (float value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. The static factory
valueOf(float)
is generally a better choice, as it is
likely to yield significantly better space and time performance.
Constructs a newly allocated Float
object that
represents the primitive float
argument.
Parameters | |
---|---|
value |
float : the value to be represented by the Float . |
Float
public Float (double value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. Instead, use the
static factory method valueOf(float)
method as follows:
Float.valueOf((float)value)
.
Constructs a newly allocated Float
object that
represents the argument converted to type float
.
Parameters | |
---|---|
value |
double : the value to be represented by the Float . |
Float
public Float (String s)
This constructor is deprecated.
It is rarely appropriate to use this constructor.
Use parseFloat(java.lang.String)
to convert a string to a
float
primitive, or use valueOf(java.lang.String)
to convert a string to a Float
object.
Constructs a newly allocated Float
object that
represents the floating-point value of type float
represented by the string. The string is converted to a
float
value as if by the valueOf
method.
Parameters | |
---|---|
s |
String : a string to be converted to a Float . |
Throws | |
---|---|
NumberFormatException |
if the string does not contain a parsable number. |
Public methods
byteValue
public byte byteValue ()
Returns the value of this Float
as a byte
after
a narrowing primitive conversion.
Returns | |
---|---|
byte |
the float value represented by this object
converted to type byte |
compare
public static int compare (float f1, float f2)
Compares the two specified float
values. The sign
of the integer value returned is the same as that of the
integer that would be returned by the call:
new Float(f1).compareTo(new Float(f2))
Parameters | |
---|---|
f1 |
float : the first float to compare. |
f2 |
float : the second float to compare. |
Returns | |
---|---|
int |
the value 0 if f1 is
numerically equal to f2 ; a value less than
0 if f1 is numerically less than
f2 ; and a value greater than 0
if f1 is numerically greater than
f2 . |
compareTo
public int compareTo (Float anotherFloat)
Compares two Float
objects numerically.
This method imposes a total order on Float
objects
with two differences compared to the incomplete order defined by
the Java language numerical comparison operators (<, <=,
==, >=, >
) on float
values.
- A NaN is unordered with respect to other
values and unequal to itself under the comparison
operators. This method chooses to define
Float.NaN
to be equal to itself and greater than all otherdouble
values (includingFloat.POSITIVE_INFINITY
). - Positive zero and negative zero compare equal
numerically, but are distinct and distinguishable values.
This method chooses to define positive zero (
+0.0f
), to be greater than negative zero (-0.0f
).
Float
objects imposed by this method is consistent with
equals; see this
discussion for details of floating-point comparison and
ordering.
Parameters | |
---|---|
anotherFloat |
Float : the Float to be compared. |
Returns | |
---|---|
int |
the value 0 if anotherFloat is
numerically equal to this Float ; a value
less than 0 if this Float
is numerically less than anotherFloat ;
and a value greater than 0 if this
Float is numerically greater than
anotherFloat . |
doubleValue
public double doubleValue ()
Returns the value of this Float
as a double
after a widening primitive conversion.
Returns | |
---|---|
double |
the float value represented by this
object converted to type double |
equals
public boolean equals (Object obj)
Compares this object against the specified object. The result
is true
if and only if the argument is not
null
and is a Float
object that
represents a float
with the same value as the
float
represented by this object. For this
purpose, two float
values are considered to be the
same if and only if the method floatToIntBits(float)
returns the identical int
value when applied to
each.
API Note:
- This method is defined in terms of
floatToIntBits(float)
rather than the==
operator onfloat
values since the==
operator does not define an equivalence relation and to satisfy the equals contract an equivalence relation must be implemented; see this discussion for details of floating-point equality and equivalence.
Parameters | |
---|---|
obj |
Object : the object to be compared |
Returns | |
---|---|
boolean |
true if the objects are the same;
false otherwise. |
See also:
floatToIntBits
public static int floatToIntBits (float value)
Returns a representation of the specified floating-point value according to the IEEE 754 floating-point "single format" bit layout.
Bit 31 (the bit that is selected by the mask
0x80000000
) represents the sign of the floating-point
number.
Bits 30-23 (the bits that are selected by the mask
0x7f800000
) represent the exponent.
Bits 22-0 (the bits that are selected by the mask
0x007fffff
) represent the significand (sometimes called
the mantissa) of the floating-point number.
If the argument is positive infinity, the result is
0x7f800000
.
If the argument is negative infinity, the result is
0xff800000
.
If the argument is NaN, the result is 0x7fc00000
.
In all cases, the result is an integer that, when given to the
intBitsToFloat(int)
method, will produce a floating-point
value the same as the argument to floatToIntBits
(except all NaN values are collapsed to a single
"canonical" NaN value).
Parameters | |
---|---|
value |
float : a floating-point number. |
Returns | |
---|---|
int |
the bits that represent the floating-point number. |
floatToRawIntBits
public static int floatToRawIntBits (float value)
Returns a representation of the specified floating-point value according to the IEEE 754 floating-point "single format" bit layout, preserving Not-a-Number (NaN) values.
Bit 31 (the bit that is selected by the mask
0x80000000
) represents the sign of the floating-point
number.
Bits 30-23 (the bits that are selected by the mask
0x7f800000
) represent the exponent.
Bits 22-0 (the bits that are selected by the mask
0x007fffff
) represent the significand (sometimes called
the mantissa) of the floating-point number.
If the argument is positive infinity, the result is
0x7f800000
.
If the argument is negative infinity, the result is
0xff800000
.
If the argument is NaN, the result is the integer representing
the actual NaN value. Unlike the floatToIntBits
method, floatToRawIntBits
does not collapse all the
bit patterns encoding a NaN to a single "canonical"
NaN value.
In all cases, the result is an integer that, when given to the
intBitsToFloat(int)
method, will produce a
floating-point value the same as the argument to
floatToRawIntBits
.
Parameters | |
---|---|
value |
float : a floating-point number. |
Returns | |
---|---|
int |
the bits that represent the floating-point number. |
floatValue
public float floatValue ()
Returns the float
value of this Float
object.
Returns | |
---|---|
float |
the float value represented by this object |
hashCode
public int hashCode ()
Returns a hash code for this Float
object. The
result is the integer bit representation, exactly as produced
by the method floatToIntBits(float)
, of the primitive
float
value represented by this Float
object.
Returns | |
---|---|
int |
a hash code value for this object. |
hashCode
public static int hashCode (float value)
Returns a hash code for a float
value; compatible with
Float.hashCode()
.
Parameters | |
---|---|
value |
float : the value to hash |
Returns | |
---|---|
int |
a hash code value for a float value. |
intBitsToFloat
public static float intBitsToFloat (int bits)
Returns the float
value corresponding to a given
bit representation.
The argument is considered to be a representation of a
floating-point value according to the IEEE 754 floating-point
"single format" bit layout.
If the argument is 0x7f800000
, the result is positive
infinity.
If the argument is 0xff800000
, the result is negative
infinity.
If the argument is any value in the range
0x7f800001
through 0x7fffffff
or in
the range 0xff800001
through
0xffffffff
, the result is a NaN. No IEEE 754
floating-point operation provided by Java can distinguish
between two NaN values of the same type with different bit
patterns. Distinct values of NaN are only distinguishable by
use of the Float.floatToRawIntBits
method.
In all other cases, let s, e, and m be three values that can be computed from the argument:
Then the floating-point result equals the value of the mathematical expression s·m·2e-150.int s = ((bits >> 31) == 0) ? 1 : -1; int e = ((bits >> 23) & 0xff); int m = (e == 0) ? (bits & 0x7fffff) << 1 : (bits & 0x7fffff) | 0x800000;
Note that this method may not be able to return a
float
NaN with exactly same bit pattern as the
int
argument. IEEE 754 distinguishes between two
kinds of NaNs, quiet NaNs and signaling NaNs. The
differences between the two kinds of NaN are generally not
visible in Java. Arithmetic operations on signaling NaNs turn
them into quiet NaNs with a different, but often similar, bit
pattern. However, on some processors merely copying a
signaling NaN also performs that conversion. In particular,
copying a signaling NaN to return it to the calling method may
perform this conversion. So intBitsToFloat
may
not be able to return a float
with a signaling NaN
bit pattern. Consequently, for some int
values,
floatToRawIntBits(intBitsToFloat(start))
may
not equal start
. Moreover, which
particular bit patterns represent signaling NaNs is platform
dependent; although all NaN bit patterns, quiet or signaling,
must be in the NaN range identified above.
Parameters | |
---|---|
bits |
int : an integer. |
Returns | |
---|---|
float |
the float floating-point value with the same bit
pattern. |
intValue
public int intValue ()
Returns the value of this Float
as an int
after
a narrowing primitive conversion.
Returns | |
---|---|
int |
the float value represented by this object
converted to type int |
isFinite
public static boolean isFinite (float f)
Returns true
if the argument is a finite floating-point
value; returns false
otherwise (for NaN and infinity
arguments).
Parameters | |
---|---|
f |
float : the float value to be tested |
Returns | |
---|---|
boolean |
true if the argument is a finite
floating-point value, false otherwise. |
isInfinite
public boolean isInfinite ()
Returns true
if this Float
value is
infinitely large in magnitude, false
otherwise.
Returns | |
---|---|
boolean |
true if the value represented by this object is
positive infinity or negative infinity;
false otherwise. |
isInfinite
public static boolean isInfinite (float v)
Returns true
if the specified number is infinitely
large in magnitude, false
otherwise.
Parameters | |
---|---|
v |
float : the value to be tested. |
Returns | |
---|---|
boolean |
true if the argument is positive infinity or
negative infinity; false otherwise. |
isNaN
public static boolean isNaN (float v)
Returns true
if the specified number is a
Not-a-Number (NaN) value, false
otherwise.
Parameters | |
---|---|
v |
float : the value to be tested. |
Returns | |
---|---|
boolean |
true if the argument is NaN;
false otherwise. |
isNaN
public boolean isNaN ()
Returns true
if this Float
value is a
Not-a-Number (NaN), false
otherwise.
Returns | |
---|---|
boolean |
true if the value represented by this object is
NaN; false otherwise. |
longValue
public long longValue ()
Returns value of this Float
as a long
after a
narrowing primitive conversion.
Returns | |
---|---|
long |
the float value represented by this object
converted to type long |
max
public static float max (float a, float b)
Returns the greater of two float
values
as if by calling Math.max
.
Parameters | |
---|---|
a |
float : the first operand |
b |
float : the second operand |
Returns | |
---|---|
float |
the greater of a and b |
See also:
min
public static float min (float a, float b)
Returns the smaller of two float
values
as if by calling Math.min
.
Parameters | |
---|---|
a |
float : the first operand |
b |
float : the second operand |
Returns | |
---|---|
float |
the smaller of a and b |
See also:
parseFloat
public static float parseFloat (String s)
Returns a new float
initialized to the value
represented by the specified String
, as performed
by the valueOf
method of class Float
.
Parameters | |
---|---|
s |
String : the string to be parsed. |
Returns | |
---|---|
float |
the float value represented by the string
argument. |
Throws | |
---|---|
NullPointerException |
if the string is null |
NumberFormatException |
if the string does not contain a
parsable float . |
See also:
shortValue
public short shortValue ()
Returns the value of this Float
as a short
after a narrowing primitive conversion.
Returns | |
---|---|
short |
the float value represented by this object
converted to type short |
sum
public static float sum (float a, float b)
Adds two float
values together as per the + operator.
Parameters | |
---|---|
a |
float : the first operand |
b |
float : the second operand |
Returns | |
---|---|
float |
the sum of a and b |
See also:
toHexString
public static String toHexString (float f)
Returns a hexadecimal string representation of the
float
argument. All characters mentioned below are
ASCII characters.
- If the argument is NaN, the result is the string
"
NaN
". - Otherwise, the result is a string that represents the sign and
magnitude (absolute value) of the argument. If the sign is negative,
the first character of the result is '
-
' ('\u002D'
); if the sign is positive, no sign character appears in the result. As for the magnitude m:- If m is infinity, it is represented by the string
"Infinity"
; thus, positive infinity produces the result"Infinity"
and negative infinity produces the result"-Infinity"
. - If m is zero, it is represented by the string
"0x0.0p0"
; thus, negative zero produces the result"-0x0.0p0"
and positive zero produces the result"0x0.0p0"
. - If m is a
float
value with a normalized representation, substrings are used to represent the significand and exponent fields. The significand is represented by the characters"0x1."
followed by a lowercase hexadecimal representation of the rest of the significand as a fraction. Trailing zeros in the hexadecimal representation are removed unless all the digits are zero, in which case a single zero is used. Next, the exponent is represented by"p"
followed by a decimal string of the unbiased exponent as if produced by a call toInteger.toString
on the exponent value. - If m is a
float
value with a subnormal representation, the significand is represented by the characters"0x0."
followed by a hexadecimal representation of the rest of the significand as a fraction. Trailing zeros in the hexadecimal representation are removed. Next, the exponent is represented by"p-126"
. Note that there must be at least one nonzero digit in a subnormal significand.
- If m is infinity, it is represented by the string
Floating-point Value | Hexadecimal String |
---|---|
1.0 | 0x1.0p0 |
-1.0 | -0x1.0p0 |
2.0 | 0x1.0p1 |
3.0 | 0x1.8p1 |
0.5 | 0x1.0p-1 |
0.25 | 0x1.0p-2 |
Float.MAX_VALUE |
0x1.fffffep127 |
Minimum Normal Value |
0x1.0p-126 |
Maximum Subnormal Value |
0x0.fffffep-126 |
Float.MIN_VALUE |
0x0.000002p-126 |
Parameters | |
---|---|
f |
float : the float to be converted. |
Returns | |
---|---|
String |
a hex string representation of the argument. |
toString
public String toString ()
Returns a string representation of this Float
object.
The primitive float
value represented by this object
is converted to a String
exactly as if by the method
toString
of one argument.
Returns | |
---|---|
String |
a String representation of this object. |
See also:
toString
public static String toString (float f)
Returns a string representation of the float
argument. All characters mentioned below are ASCII characters.
- If the argument is NaN, the result is the string
"
NaN
". - Otherwise, the result is a string that represents the sign and
magnitude (absolute value) of the argument. If the sign is
negative, the first character of the result is
'
-
' ('\u002D'
); if the sign is positive, no sign character appears in the result. As for the magnitude m:- If m is infinity, it is represented by the characters
"Infinity"
; thus, positive infinity produces the result"Infinity"
and negative infinity produces the result"-Infinity"
. - If m is zero, it is represented by the characters
"0.0"
; thus, negative zero produces the result"-0.0"
and positive zero produces the result"0.0"
. - If m is greater than or equal to 10-3 but
less than 107, then it is represented as the
integer part of m, in decimal form with no leading
zeroes, followed by '
.
' ('\u002E'
), followed by one or more decimal digits representing the fractional part of m. - If m is less than 10-3 or greater than or
equal to 107, then it is represented in
so-called "computerized scientific notation." Let n
be the unique integer such that 10n ≤
m < 10n+1; then let a
be the mathematically exact quotient of m and
10n so that 1 ≤ a < 10.
The magnitude is then represented as the integer part of
a, as a single decimal digit, followed by
'
.
' ('\u002E'
), followed by decimal digits representing the fractional part of a, followed by the letter 'E
' ('\u0045'
), followed by a representation of n as a decimal integer, as produced by the methodInteger.toString(int)
.
- If m is infinity, it is represented by the characters
float
. That is, suppose that x is the
exact mathematical value represented by the decimal
representation produced by this method for a finite nonzero
argument f. Then f must be the float
value nearest to x; or, if two float
values are
equally close to x, then f must be one of
them and the least significant bit of the significand of
f must be 0
.
To create localized string representations of a floating-point
value, use subclasses of NumberFormat
.
Parameters | |
---|---|
f |
float : the float to be converted. |
Returns | |
---|---|
String |
a string representation of the argument. |
valueOf
public static Float valueOf (String s)
Returns a Float
object holding the
float
value represented by the argument string
s
.
If s
is null
, then a
NullPointerException
is thrown.
Leading and trailing whitespace characters in s
are ignored. Whitespace is removed as if by the String.trim()
method; that is, both ASCII space and control
characters are removed. The rest of s
should
constitute a FloatValue as described by the lexical
syntax rules:
where Sign, FloatingPointLiteral, HexNumeral, HexDigits, SignedInteger and FloatTypeSuffix are as defined in the lexical structure sections of The Java Language Specification, except that underscores are not accepted between digits. If
- FloatValue:
- Signopt
NaN
- Signopt
Infinity
- Signopt FloatingPointLiteral
- Signopt HexFloatingPointLiteral
- SignedInteger
- HexFloatingPointLiteral:
- HexSignificand BinaryExponent FloatTypeSuffixopt
- HexSignificand:
- HexNumeral
- HexNumeral
.
0x
HexDigitsopt.
HexDigits0X
HexDigitsopt.
HexDigits
- BinaryExponent:
- BinaryExponentIndicator SignedInteger
- BinaryExponentIndicator:
p
P
s
does not have the form of
a FloatValue, then a NumberFormatException
is thrown. Otherwise, s
is regarded as
representing an exact decimal value in the usual
"computerized scientific notation" or as an exact
hexadecimal value; this exact numerical value is then
conceptually converted to an "infinitely precise"
binary value that is then rounded to type float
by the usual round-to-nearest rule of IEEE 754 floating-point
arithmetic, which includes preserving the sign of a zero
value.
Note that the round-to-nearest rule also implies overflow and
underflow behaviour; if the exact value of s
is large
enough in magnitude (greater than or equal to (MAX_VALUE
+ ulp(MAX_VALUE)
/2),
rounding to float
will result in an infinity and if the
exact value of s
is small enough in magnitude (less
than or equal to MIN_VALUE
/2), rounding to float will
result in a zero.
Finally, after rounding a Float
object representing
this float
value is returned.
To interpret localized string representations of a
floating-point value, use subclasses of NumberFormat
.
Note that trailing format specifiers, specifiers that
determine the type of a floating-point literal
(1.0f
is a float
value;
1.0d
is a double
value), do
not influence the results of this method. In other
words, the numerical value of the input string is converted
directly to the target floating-point type. In general, the
two-step sequence of conversions, string to double
followed by double
to float
, is
not equivalent to converting a string directly to
float
. For example, if first converted to an
intermediate double
and then to
float
, the string
"1.00000017881393421514957253748434595763683319091796875001d"
results in the float
value
1.0000002f
; if the string is converted directly to
float
, 1.0000001f
results.
To avoid calling this method on an invalid string and having
a NumberFormatException
be thrown, the documentation
for Double.valueOf
lists a regular
expression which can be used to screen the input.
Parameters | |
---|---|
s |
String : the string to be parsed. |
Returns | |
---|---|
Float |
a Float object holding the value
represented by the String argument. |
Throws | |
---|---|
NumberFormatException |
if the string does not contain a parsable number. |
valueOf
public static Float valueOf (float f)
Returns a Float
instance representing the specified
float
value.
If a new Float
instance is not required, this method
should generally be used in preference to the constructor
Float(float)
, as this method is likely to yield
significantly better space and time performance by caching
frequently requested values.
Parameters | |
---|---|
f |
float : a float value. |
Returns | |
---|---|
Float |
a Float instance representing f . |